c9200760da
Check for valid block size directly by validating s_log_block_size; we were doing this in two places. First, by calculating blocksize via BLOCK_SIZE << s_log_block_size, and then checking that the blocksize was valid. And then secondly, by checking s_log_block_size directly. The first check is not reliable, and can trigger an UBSAN warning if s_log_block_size on a maliciously corrupted superblock is greater than 22. This is harmless, since the second test will correctly reject the maliciously fuzzed file system, but to make syzbot shut up, and because the two checks are duplicative in any case, delete the blocksize check, and move the s_log_block_size earlier in ext4_fill_super(). Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reported-by: syzbot+345b75652b1d24227443@syzkaller.appspotmail.com
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.